1. Technical Field
The present invention relates to a manufacturing apparatus for a liquid crystal device, a manufacturing method for a liquid crystal device, a liquid crystal device and electronic device.
2. Related Art
A liquid crystal device has been used as a photo-modulation section in a projection display device such as a liquid crystal projector, etc.
Such a liquid crystal device includes a sealant arranged at the periphery between a pair of substrates and a liquid crystal layer sealed at its center.
Electrodes for applying a voltage to the liquid crystal layer are formed on the side of an inner surface of the pair of substrates, and an oriented film for controlling the orientation of liquid crystal molecules when applying a non-selective voltage is formed on the side of the inner surface of the electrodes.
By such a constitution, the liquid crystal device modulates the light of a light source based on the orientation change of the liquid crystal molecules when applying a non-selective voltage or selective voltage to form the light of an image.
An oriented film subjected to a rubbing treatment is generally used as the above-mentioned oriented film on the surface of a polymer film made of polyimides to which a side-chain alkyl group, etc, has been added.
The rubbing treatment section of a polymer is oriented in a pre-determined direction by rubbing the surface of a polymer film in a pre-determined direction with a roller having a soft cloth.
Liquid crystal molecules are arranged along an orienting high polymer due to an intermolecular interaction between the orienting high molecules and the liquid crystal molecules.
Therefore, liquid crystal molecules can be oriented in a pre-determined direction when a non-selective voltage is applied.
A pre-tilt can be given to a liquid crystal molecule by a side-chain alkyl group.
However, when a liquid crystal device fitted with such an organic oriented film is adopted as the photo-modulation section of a projector, there is concern that the oriented film will gradually degrade due to strong light radiated from a light source or heat.
There is further concern that the orientation control function of liquid crystal molecules is reduced and the display quality of the liquid crystal projector will deteriorate after extended use, e.g., the liquid crystal molecules cannot be arrayed at a desired pre-tilt angle.
Accordingly, as disclosed in Japanese Unexamined Patent Application, First Publication No. 2002-277879, the use of an oriented film made of an inorganic material excellent in light resistance and heat resistance has been proposed.
As a manufacturing method for such an inorganic oriented film, for example, a silicon oxide (SiO2) film formed by an oblique evaporation process is known.
The technique of Japanese Unexamined Patent Application, First Publication No. 2002-277879 overcomes the technical problem in that, if an inorganic material is obliquely deposited as it is, especially when a stepped portion is formed at the under portion of an oriented film due to pixel electrode wiring, etc., poor evaporation areas (evaporation irregularities or no evaporation) of inorganic material form in the vicinity of the stepped portion.
In the technique of Japanese Unexamined Patent Application, First Publication No. 2002-277879, especially a first obliquely inorganic evaporated film and a second obliquely inorganic evaporated film are formed while azimuth directions are differed from each other.
When an inorganic oriented film is formed by the oblique evaporation process, it is necessary to control the incidence angle of an oriented film material to form the oriented film in a desired oriented state.
As a technique for controlling the incidence angle of an orientation material, Japanese Unexamined Patent Application, First Publication No. 2002-365639 is known.
According to this technique, a shielding plate having a slit is arranged between an oriented film material and a substrate, through which a desired oriented film is formed by selective evaporation at a pre-determined incidence angle.
In addition to the technique shown in Japanese Unexamined Patent Application, First Publication No. 2002-277879, for example, it is also considered that a base film that also serves as a flattening layer is formed as an under portion of an oriented film, by which a stepped portion is eliminated to some extent. An inorganic film is then formed thereon in order to solve the technical problem caused by the formation of a stepped portion in the under portion of the oriented film as described above.
However, when the base film that also serves as a flattening layer is formed, it is necessary to separately prepare an apparatus for the forming of the base film and an apparatus for the forming of the oriented film, creating the new problem of increasing apparatus cost.
In the technique described in Japanese Unexamined Patent Application, First Publication No. 2002-365639, the forming of the oriented film includes controlling the incidence angle of the oriented film by passing the material of the oriented film sublimated from an evaporation source through the slit of the shielding plate so as to flow only part of the material at a pre-determined angle.
Therefore, in the forming of the oriented film, other part of sublimated material which does not pass through the slit of the shielding plate is wasted.
There is a problem in that the usage efficiency of material is poor.